Ribonuclease-Gold Labels Heparin in Human Mast Cell Granules: New Use for an Ultrastructural Enzyme Affinity Technique

We evaluated an enzyme affinity-gold ultrastructural technique designed to identify RNA-rich structures, based on an RNase-gold (R-G) probe in human mast cells (HMCs). As expected, the R-G technique labeled RNA-containing ribosomes and nucleoli in HMCs. The heparin-rich secretory granules in HMCs were also labeled. Extensive studies revealed that HMCs isolated from lung or skin and sustained in short-term cultures, derived de novo in growth factor-supplemented cord blood cell cultures, or present in vivo in multiple sites all shared this property. We performed a large number of controls designed to examine the HMC granule binding characteristics of gold alone, of irrelevant protein- or enzyme-gold reagents, of the role of charge and enzyme activity after various enzyme digestions, after blocking with macromolecules, after exposure to inhibitors of RNase, of heparin, or to irrelevant enzyme inhibitors, including staining of macromolecule-containing test agar blocks and a variety of combined absorption and digestion experiments of the binding of R-G to HMC granules. These studies established that the R-G method detected heparin in this site in conventionally prepared, well-preserved electron microscopic samples. These findings demonstrate a new use for this enzyme affinity-gold technique in mast cell biology, based on the known property of heparin as an inhibitor of RNase.

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CONCOMITANT SYNTHESIS OF MEMBRANE PROTEIN AND EXPORTABLE PROTEIN OF THE SECRETORY GRANULE IN RAT PAROTID GLAND

The Journal of Cell Biology ◽

10.1083/jcb.50.1.187 ◽

1971 ◽

Vol 50 (1) ◽

pp. 187-200 ◽

Cited By ~ 86

Author(s):

Abraham Amsterdam ◽

Michael Schramm ◽

Itzhak Ohad ◽

Yoram Salomon ◽

Zvi Selinger

Keyword(s):

Amino Acids ◽

Secretory Granule ◽

De Novo ◽

Secretory Granules ◽

Specific Radioactivity ◽

Staining Intensity ◽

Granule Membrane ◽

Rat Parotid ◽

Cell Fractions

After enzyme secretion the membrane of the secretory granule, which had been fused to the cell membrane, was resorbed into the cell. Experiments were therefore carried out to test whether formation of new secretory granules involves reutilization of the resorbed membrane or synthesis of a new membrane, de novo, from amino acids. Incorporation of amino acids-14C into proteins of various cell fractions was measured in vivo, 30, 120, and. 300 min after labeling. At all times the specific radioactivity of the secretory granule membrane was about equal to that of the granule's exportable content. At 120 and 300 min the specific radioactivity of the granule membrane and of the granule content was much higher than that of any other subcellular fraction. It is therefore concluded that the protein of the membrane is synthesized de novo concomitantly with the exportable protein. The proteins of the granule membrane could be distinguished from those of the granule content by gel electrophoresis. All major bands were labeled proportionately to their staining intensity. The amino acid composition of the secretory granule membrane was markedly different from that of the granule's content and also from that of the mitochondrial membrane. The granule membrane showed a high proline content, 30 moles/100 moles amino acids. The analyses show that the radioactivity of the granule membrane is indeed inherent in its proteins and is not due to contamination by other fractions. The possibility is considered that the exportable protein leaves the endoplasmic reticulum already enveloped by the newly synthesized membrane.

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Development of both human connective tissue-type and mucosal-type mast cells in mice from hematopoietic stem cells with identical distribution pattern to human body

Blood ◽

10.1182/blood-2003-04-1160 ◽

2004 ◽

Vol 103 (3) ◽

pp. 860-867 ◽

Cited By ~ 39

Author(s):

Naotomo Kambe ◽

Hidefumi Hiramatsu ◽

Mika Shimonaka ◽

Hisanori Fujino ◽

Ryuta Nishikomori ◽

...

Keyword(s):

Stem Cells ◽

Mast Cell ◽

Mast Cells ◽

Hematopoietic Stem Cells ◽

Cell Development ◽

Tissue Type ◽

Human Mast Cell ◽

Hematopoietic Stem ◽

Nog Mice

Abstract The transplantation of primitive human cells into sublethally irradiated immune-deficient mice is the well-established in vivo system for the investigation of human hematopoietic stem cell function. Although mast cells are the progeny of hematopoietic stem cells, human mast cell development in mice that underwent human hematopoietic stem cell transplantation has not been reported. Here we report on human mast cell development after xenotransplantation of human hematopoietic stem cells into nonobese diabetic severe combined immunodeficient \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \((\mathrm{NOD{/}SCID}){/}{\gamma}_{\mathrm{c}}^{null}\) \end{document} (NOG) mice with severe combined immunodeficiency and interleukin 2 (IL-2) receptor γ-chain allelic mutation. Supported by the murine environment, human mast cell clusters developed in mouse dermis, but they required more time than other forms of human cell reconstitution. In lung and gastric tract, mucosal-type mast cells containing tryptase but lacking chymase located on gastric mucosa and in alveoli, whereas connective tissue-type mast cells containing both tryptase and chymase located on gastric submucosa and around major airways, as in the human body. Mast cell development was also observed in lymph nodes, spleen, and peritoneal cavity but not in the peripheral blood. Xenotransplantation of human hematopoietic stem cells into NOG mice can be expected to result in a highly effective model for the investigation of human mast cell development and function in vivo.

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Ultrastructural Similarity between Bat and Human Mast Cell Secretory Granules

International Archives of Allergy and Immunology ◽

10.1159/000236416 ◽

1993 ◽

Vol 100 (3) ◽

pp. 230-233 ◽

Cited By ~ 3

Author(s):

Sônia Maria Oliani ◽

Ithamar Vugman ◽

Maria Célia Jamur

Keyword(s):

Mast Cell ◽

Secretory Granules ◽

Human Mast Cell

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The Role of Nucleophosmin In Hematopoietic Stem Cells and the Pathogenesis of Myelodysplastic Syndrome

Blood ◽

10.1182/blood.v116.21.95.95 ◽

2010 ◽

Vol 116 (21) ◽

pp. 95-95 ◽

Cited By ~ 1

Author(s):

Keisuke Ito ◽

Paolo Sportoletti ◽

John G Clohessy ◽

Grisendi Silvia ◽

Pier Paolo Pandolfi

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Myelodysplastic Syndrome ◽

Cell Biology ◽

De Novo ◽

Stem Cell Biology ◽

Hematopoietic Stem

Abstract Abstract 95 Myelodysplastic syndrome (MDS) is an incurable stem cell disorder characterized by ineffective hematopoiesis and an increased risk of leukemia transformation. Nucleophosmin (NPM) is directly implicated in primitive hematopoiesis, the pathogenesis of hematopoietic malignancies and more recently of MDS. However, little is known regarding the molecular role and function of NPM in MDS pathogenesis and in stem cell biology. Here we present data demonstrating that NPM plays a critical role in the maintenance of hematopoietic stem cells (HSCs) and the transformation of MDS into leukemia. NPM is located on chromosome 5q and is frequently lost in therapy-related and de novo MDS. We have previously shown that Npm1 acts as a haploinsufficient tumor suppressor in the hematopoietic compartment and Npm1+/− mice develop a hematologic syndrome with features of human MDS, including increased susceptibility to leukemogenesis. As HSCs have been demonstrated to be the target of the primary neoplastic event in MDS, a functional analysis of the HSC compartment is essential to understand the molecular mechanisms in MDS pathogenesis. However, the role of NPM in adult hematopoiesis remains largely unknown as Npm1-deficiency leads to embryonic lethality. To investigate NPM function in adult hematopoiesis, we have generated conditional knockout mice of Npm1, using the Cre-loxP system. Analysis of Npm1 conditional mutants crossed with Mx1-Cre transgenic mice reveals that Npm1 plays a crucial role in adult hematopoiesis and ablation of Npm1 in adult HSCs leads to aberrant cycling and followed by apoptosis. Analysis of cell cycle status revealed that HSCs are impaired in their ability to maintain quiescence after Npm1-deletion and are rapidly depleted in vivo as well as in vitro. Competitive reconstitution assay revealed that Npm1 acts cell-autonomously to maintain HSCs. Conditional inactivation of Npm1 leads to an MDS phenotype including a profoundly impaired ability to differentiate into cells of the erythroid lineage, megakaryocyte dyspoiesis and centrosome amplification. Furthermore, Npm1 loss evokes a p53-dependent response and Npm1-deleted HSCs undergo apoptosis in vivo and in vitro. Strikingly, transfer of the Npm1 mutation into a p53-null background rescued the apoptosis of Npm1-ablated HSCs and resulted in accelerated transformation to an aggressive and lethal form of acute myeloid leukemia. Our findings highlight the crucial role of NPM in stem cell biology and identify a new mechanism by which MDS can progress to leukemia. This has important therapeutic implications for de novo MDS as well as therapy-related MDS, which is known to rapidly evolve to leukemia with frequent loss or mutation of TRP53. Disclosures: No relevant conflicts of interest to declare.

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High-resolution tracking of cell division demonstrates differential effects of TH1 and TH2 cytokines on SCF-dependent human mast cell production in vitro:correlation with apoptosis and Kit expression

Blood ◽

10.1182/blood-2004-07-2838 ◽

2005 ◽

Vol 105 (2) ◽

pp. 592-599 ◽

Cited By ~ 34

Author(s):

Marianna Kulka ◽

Dean D. Metcalfe

Keyword(s):

Mast Cell ◽

Cell Division ◽

Mast Cells ◽

Cell Number ◽

Interleukin 4 ◽

Human Mast Cell ◽

T Helper 1 ◽

Cell Production ◽

Ifn Γ

Abstract T-helper 1 (TH1) (interferon-γ [IFN-γ]) and TH2 (interleukin-4 [IL-4] and IL-5) cytokines have been variably reported to alter human mast cell numbers in complex culture systems. The effects of these cytokines on the kinetics of cell division and cell death are unknown, and their effect on mast cell behavior is relevant to anticipate the consequences of in vivo strategies that alter cytokine levels. To determine the effect of these cytokines on stem cell factor (SCF)–dependent human mast cell production, we used highresolution tracking of cell division and correlated the results with cell apoptosis, expression of Kit, and mast cell degranulation. When IFN-γ, IL-5, or IL-4 was administered over 8 weeks, we found each cytokine decreased the mast number through a different mechanism. IFN-γ inhibited early progenitor cell division, IL-4 down-regulated early Kit expression, and IL-5 blocked later cell division. Further, IL-4 and IFN-γ had the greatest suppressive effect on degranulation and FcϵRI expression. When these cytokines were administered to mature mast cells, IFN-γ and IL-5 had no effect on degranulation and cell division, but IL-4 induced division and potentiated FcϵRI-mediated degranulation. Thus, exposure of human mast cells to IL-4, IL-5, and IFN-γ during growth and differentiation generally down-regulated mast cell number and function, whereas IL-4 increased mature mast cell division and degranulation.

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Recombinant human stem cell factor (kit ligand) promotes human mast cell and melanocyte hyperplasia and functional activation in vivo.

Journal of Experimental Medicine ◽

10.1084/jem.183.6.2681 ◽

1996 ◽

Vol 183 (6) ◽

pp. 2681-2686 ◽

Cited By ~ 190

Author(s):

J J Costa ◽

G D Demetri ◽

T J Harrist ◽

A M Dvorak ◽

D F Hayes ◽

...

Keyword(s):

Mast Cell ◽

Stem Cell ◽

Mast Cells ◽

Stem Cell Factor ◽

Serum Levels ◽

Human Mast Cell ◽

Tyrosine Kinase Receptor ◽

Kit Ligand ◽

Wheal And Flare

Stem cell factor (SCF), also known as mast cell growth factor, kit ligand, and steel factor, is the ligand for the tyrosine kinase receptor (SCFR) that is encoded by the c-kit proto-oncogene. We analyzed the effects of recombinant human SCF (r-hSCF, 5-50 micrograms/kg/day, injected subcutaneously) on mast cells and melanocytes in a phase I study of 10 patients with advanced breast carcinoma. A wheal and flare reaction developed at each r-hSCF injection site; by electron microscopy, most dermal mast cells at these sites exhibited extensive, anaphylactic-type degranulation. A 14-d course of r-hSCF significantly increased dermal mast cell density at sites distant to those injected with the cytokine and also increased both urinary levels of the major histamine metabolite, methyl-histamine, and serum levels of mast cell alpha-tryptase. Five subjects developed areas of persistent hyperpigmentation at r-hSCF injection sites; by light microscopy, these sites exhibited markedly increased epidermal melanization and increased numbers of melanocytes. The demonstration that r-hSCF can promote both the hyperplasia and the functional activation of human mast cells and melanocytes in vivo has implications for our understanding of the role of endogenous SCF in health and disease. These findings also indicate that the interaction between SCF and its receptor represents a potential therapeutic target for regulating the numbers and functional activity of both mast cells and cutaneous melanocytes.

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Inhibitory effect of colchicines on amylase secretion by rat parotid glands: possible localization in the golgi area

The Journal of Cell Biology ◽

10.1083/jcb.73.3.578 ◽

1977 ◽

Vol 73 (3) ◽

pp. 578-593 ◽

Cited By ~ 58

Author(s):

C Patzelt ◽

D Brown ◽

B Jeanrenaud

Keyword(s):

De Novo ◽

Secretory Granules ◽

Inhibitory Effect ◽

Binding Activity ◽

Amylase Secretion ◽

Parotid Glands ◽

Secretory Material ◽

Delayed Effect ◽

Rat Parotid

Colchicine inhibited amylase secretion by isolated rat parotid glands only 6 h after administration of the drug in vivo. This delayed effect was not the result of the inability of the drug to reach its reaction site. When parotid glands were emptied of their secretory granules by isoproterenol treatment, the subsequent replenishment of cells with granules was inhibited by colchicines. Colchicine concomitantly produced alterations of the Golgi complexes, the cisternae of which were reduced in size and surrounded by clusters of microvesicles. Incubation of parotid glands with colchicines for prolonged durations failed to alter stored amylase secretion as stimulated by isoproterenol, but it inhibited the release of de novo synthesized enzyme. Another colchicines-binding activity, firmly bound to the particular fraction of homogenates, was found, of which a part may represent membrane located microtubular protein. An assembly-disassembly cycle of microtubules appears to exist in the parotid gland, as in the liver. However, only 14 percent of tubulin was found to be polymerized as microtubules in parotid glands as opposed to 40 percent in the liver. The present data suggest that colchicine primarily inhibits the transfer of secretory material towards or away from the Golgi complexes but not the hormone-stimulated secretion of stored amylase.

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Recent advances in mast cell activation and regulation

F1000Research ◽

10.12688/f1000research.22037.1 ◽

2020 ◽

Vol 9 ◽

pp. 196 ◽

Cited By ~ 4

Author(s):

Hwan Soo Kim ◽

Yu Kawakami ◽

Kazumi Kasakura ◽

Toshiaki Kawakami

Keyword(s):

Mast Cell ◽

Mast Cells ◽

Cell Activation ◽

De Novo ◽

Immunoglobulin E ◽

Secretory Granules ◽

Structural Features ◽

Mast Cell Activation ◽

Dependent Manner ◽

Drug Induced

Mast cells are innate immune cells that intersect with the adaptive immunity and play a crucial role in the initiation of allergic reactions and the host defense against certain parasites and venoms. When activated in an allergen- and immunoglobulin E (IgE)-dependent manner, these cells secrete a large variety of allergenic mediators that are pre-stored in secretory granules or de novo–synthesized. Traditionally, studies have predominantly focused on understanding this mechanism of mast cell activation and regulation. Along this line of study, recent studies have shed light on what structural features are required for allergens and how IgE, particularly anaphylactic IgE, is produced. However, the last few years have seen a flurry of new studies on IgE-independent mast cell activation, particularly via Mrgprb2 (mouse) and MRGPRX2 (human). These studies have greatly advanced our understanding of how mast cells exert non-histaminergic itch, pain, and drug-induced pseudoallergy by interacting with sensory neurons. Recent studies have also characterized mast cell activation and regulation by interleukin-33 (IL-33) and other cytokines and by non-coding RNAs. These newly identified mechanisms for mast cell activation and regulation will further stimulate the allergy/immunology community to develop novel therapeutic strategies for treatment of allergic and non-allergic diseases.

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